Game of Thrones Season 6 starts on Sunday. Discover how the previous seasons of the show's VFX were created by Image Engine, Mackevision, Rodeo FX and Rhythm and Hues.

Can't wait to get your fix of Game of Thrones before the Season 6 starts on Sunday April 24 (at 2am in the UK on Sky Atlantic, or again at 9pm on Monday April 25 - or just download it from Sky+/Sky Go). Here you can watch videos showing Image Engine, Mackevision, Rodeo FX and Rhythm and Hues' work on season 5. The videos also shows how much of architecture of the show is real, filmed in cities in Croatia and Spain and across the Irish wilderness.

We kick off with Rodeo FX, which has also provided in-depth details of how they created key sequences. You can watch the other studios' VFX breakdowns below this.

Game of Thrones Season 5 VFX: Rodeo VFX

Rodeo FX's work on Game of Thrones season 5 included tentpole sequences including the Meereen temple (and the destruction of the harpy above it), the Smoking Sea of Valyria and the slave-owning city Volantis.

From Rodeo FX about the destruction of the harpy statue in Mereen:

The first episode of Season 5 shows the destruction of the Harpy atop the pyramid that Rodeo FX created last season for the fictional world of Meereen. A group of the Unsullied has tied ropes to the golden statue and pulls it down. The Harpy topples, sliding down the massive structure, smashing bricks and throwing up sand in its wake, before it lands on its side on the ground. The scale is massive, with huge objects colliding, throwing up chunks of brick and dust.

“This was a huge CG build and complex work for TV,” said Matthew Rouleau (below), VFX supervisor on the show for Rodeo FX. “It is challenging because we’re aiming for feature film quality, but the schedule is not the same as on features.”

Rodeo FX worked from previs for the whole sequence created by Joe Bauer, the VFX supervisor across the whole series. The artists added elements to make the fully CG scene look more alive and complex. The studio used matte paintings for the background.

“We built on last year’s work,” Rouleau said. “Needing close ups of the pyramid meant we had to build it up brick by brick. Every brick was modeled and textured independently.”

Rodeo FX blended live action shots with effects, compositing them together. Using its experience with a pivotal scene from its previous work on Unbroken, when a B24 bomber crash lands on a runway, the team was able to create a realistic feel of sand flying using practical elements that it shot in its Montreal studio.

From Rodeo FX about building the ruins of Old Valyria:

With a bound and beaten Tyrion (Peter Dinklage) recovering in the hull of his small open sailboat, Jorah (Iain Glen) steers toward the ruins of Old Valyria on their way to Meereen and Queen Daenerys. The mood of the scene in Episode 5, “Kill the Boy”, is heightened by the Smoking Sea, mist off the water, and the collapsing ruins of once-great buildings. All of this closes in on them as they approach an aqueduct topped with what appear to be stone statues.

In fact, almost all of this environment – except for some trees, the actors, and their boat – is digital matte paintings, projected on simple geometry. This mysterious environment was created by Rodeo FX in its L.A. and Montreal studios under the direction of Deak Ferrand, Senior Matte Painter at Rodeo FX, who worked closely with Bauer.

“Deak and Rodeo FX worked on top-of-frame grabs of the cut sequence and really laid out Old Valyria from scratch, using our simple guideline to make it into a super-advanced Angkor Wat,” said Bauer, referring to the large temple complex in Cambodia. “We'd done internal design work on the aqueduct ruin where the encounter with the Stone Men happens – and a rough look at the distant ruins far beyond – but it became very much what you saw in the episode in Deak's and Rodeo's hands.”

“We started with the live plates, which were simply the boat on the river with some trees and a partial set of the aqueduct,” explained Ferrand. “We conceptualised all the shots on stills, including a big aqueduct concept. From there, we moved quickly to digital matte painting.”

Ferrand and his team added trees, changed the entire sky, and did water extensions in CG. The overhead shot at the beginning of the scene, as Tyrion regains consciousness, is a complete CG replacement. Rodeo FX reframed some of the plates to give the scope of the sequence, at times resizing them because they were too big in the frame. They also added mist enhancement coming off the river, which adds to the spooky feel.

“Once we’d designed this ruined city, the main challenge of this sequence was the progression as the boat travels toward the aqueduct,” explained Ferrand. “It’s one thing to create shots that are not already put together. But here, what is in the background in the first shot becomes the foreground of the tenth shot.”

Ferrand worked side by side with Bauer on the look of the city. Since Old Valyria flourished during the time of dragons, they considered adding dragon statues and iconographies on top of the ruined structures. They were not satisfied with the overall impression, so they chose to remove any references related to dragons. It is only when Tyrion and Jorah pass the first gate and reach the aqueduct that there is resolution to their travels. The brooding dynamism of this digital environment comes to life as the Stone Men attack.

Game of Thrones Season 5 VFX: Image Engine

Game of Thrones Season 5 VFX: Rhythm and Hues

Game of Thrones Season 5 VFX: Mackevision

You can see a breakdown of German VFX studio Mackevision's work on Season 5 above, and watch an interview with Mackevision's CEO about working on Game of Thrones below.

More Game of Thrones Season 5 VFX breakdowns

If you want to know more, watch these videos created by Wired and iO9.